Although I imagine many people take it as one. That said, their number is acceptable for summer use when self-discharge rates are much higher than in winter, particularly if the boat is down south, like in CT or NY where it gets way too hot. Personally I don't know how anyone can live in the south. Note that my definition of the south starts at Rockland. The summer weather in the deep south, i.e., Portland, sounds like hell to me.